Each of your feet are densely covered with about 250,000 eccrine sweat glands, making feet one of the sweatiest places on your body. Performance fabrics help absorb and disperse all that moisture. Here are your most common choices:
Merino wool: The fine, itch-free fibers of merino wool have virtually replaced the scratchy ragg-wool socks previous generations used. Their biggest advantage is that they are thermostatic (temperature-regulating), so your feet stay comfortable in a wide range of temperatures. Wool can absorb up to 30% of its weight in water, which helps feet remain dry in most conditions.
- Pros: Comfortable in cool or warm conditions, absorbs and wicks moisture, cushions, doesn't itch like ragg wool.
- Cons: Dries a bit slower than synthetics, more expensive.
Synthetics: Several materials are often combined or used in select areas of the sock for greater comfort and fit. Nylon and Lycra® spandex help socks retain their shape, create a snug fit and, in some sock styles, provide arch support. CoolMax® polyester, Wickspun™ acrylic and Isolfil®polypropylene are commonly used fibers that wick away moisture to keep your feet dry and prevent blisters.
- Pros: Durable, dries fast, wicks moisture, cushions.
- Cons: Less comfortable in hot conditions, insulation reduced when wet.
Ingeo™: Pronounced IN-gee-oh, this corn-based polylactic acid (or PLA) fiber acts similarly to polyester but is an eco-friendly alternative.
- Pros: Made from a renewable resource, recyclable, wicks moisture, controls odors.
- Cons: Less durable than other fabrics; can only be commercially composted.
Silk: This natural insulator is used in some liner socks. It wicks moisture and offers a smooth texture against the skin.
- Pros: Lightweight, wicks moisture, comfortable against skin.
- Cons: Less durable than other fabrics.
Cotton: Cotton is not recommended for active uses, so you'll find few or no such styles at REI. The problem with 100% cotton socks is that they absorb sweat, saturate quickly and dry slowly, which is a perfect recipe for blisters.
- Pros: Comfortable for non-active uses, inexpensive.
- Cons: Not recommended for active wear.